


all that you touch

by flirtygaybrit



Category: DC Extended Universe, Justice League (2017)
Genre: Black Kryptonite, Choose Your Own Ending, Horror, M/M
Language: English
Status: Completed
Published: 2018-08-17
Updated: 2018-08-17
Packaged: 2019-06-14 17:52:47
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 3
Words: 9,216
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/15394188
Author URL: https://archiveofourown.org/users/flirtygaybrit/pseuds/flirtygaybrit
Summary: A secret room, a mirror made of black glass, a dark figure with a face not its own, and a single decision that may alter the course of history. Remember:all that you touch, you change.





	1. The Mirror

**Author's Note:**

  * For [Lord Vitya (ProtoDan)](https://archiveofourown.org/users/ProtoDan/gifts).



> This fic is a perfect combination of a few ideas that I've wanted to execute for quite some time, and your letter did include an open invitation for a horror AU. I sincerely hope you enjoy it, and I hope that you make the right decision. ;)
> 
> Title and summary line from Rusty Lake's Cube Escape: Seasons.
> 
> To the reader: I highly recommend using the **chapter-by-chapter** viewing format, as each ending is contained separately in its own chapter and it is possible that viewing the work as a whole (or even clicking 'next chapter') could spoil the experience. Just follow the story. When it comes time to make your choice, chosen the appropriate chapter. You’ll know what to do.

It comes, like many of the events that have destabilized Clark’s life, from the belly of the Kryptonian ship in the middle of the night.

The vessel’s vast, echoing hallways are near silent even to Clark’s ears, though he supposes it would be more disturbing if they weren’t. He’s working into the early hours of the morning now, and it’s already been a while since the rest of the League shuffled off to various corners of the city to bed down until daybreak. 

But Clark isn’t the only one in the ship tonight, or even most nights. Bruce is still here, too, wandering somewhere in the opposite end. Clark has given up trying to tell Bruce to go home because while Bruce doesn’t get half as much sleep as he should, he’s a habitual night owl, and a stubborn one at that. He’ll continue to make excuses to stay in the ship as long as Clark is here, and Clark will find a reason not to kick him out of the only place in the world where he can get some peace and quiet.

“Hey. Have you seen this?”

Bruce’s voice carries through the halls like a physical presence. He’s not shouting, nor does his voice carry any hint of urgency, but Clark can hear him clearly even from the opposite side of the ship, and it draws his attention immediately. 

It’s rare that Bruce doesn’t address him by name. With the others he’s usually just ‘Superman’, since he usually only sees them when he’s suited up, but Bruce calls him Clark regardless of dress or situation. It doesn’t bother Clark, really, though sometimes he can’t help wondering if maybe Bruce has conveniently forgotten the importance of secrecy, or if he simply likes the way Clark’s name feels in his mouth. Clark could sort of maybe understand that. It feels like most of his sentences begin with ‘Bruce’, somehow, like it’s become habit to ensure that he’s speaking specifically to Bruce and not to his alter ego, and sometimes it’s comforting to say Bruce’s name and hear his own in return.

If saying one’s name can be considered an intimacy, Clark would consider them very well-acquainted.

Clark makes his way to the far end of the ship in the span of a few seconds, an act which is a novelty in itself because the Kryptonian design creates a sanctuary in which his powers are, while useful, rendered unnecessary. The scout ship molds itself to his whims, capable of melting walls into rounded doors that open smoothly or causing walls to shimmer and become translucent when he feels like looking into the room adjacent. This time it creates a series of doorways for him, allowing for an an impossible architectural detour that takes him through a series of great chambers and empty hallways until suddenly Bruce is next to him, and he realizes that they’re in a room that he hasn’t seen before.

It’s hard to call any closed spaces within the ship a room, but he’s pretty sure that’s what this one is. It’s a small chamber, no larger than a common household bathroom, maybe a eight feet from floor to ceiling with aesthetically pleasing designs swirling over the walls. There’s a sealed doorway embedded in the wall to Clark’s right, which means it’s a doorway that was built intentionally and not simply created for a single-use passage.

The door Clark passed through disappears with a quiet sound, and the room goes silent.

“...No,” Clark says. He glances around, but there’s nothing of note in the room, no furniture or weapon caches or pods filled with long-dead Kryptonian corpses. It’s kind of a relief to find a room that’s just empty, actually. Many of the things he’s discovered on this ship have been dangerous, depressing, or a sad mix of both. “You mean the room? I didn’t even know this was here. I’m starting to think this ship just makes up things for us to look at when we get bored.”

Bruce hums thoughtfully, and when Clark glances at him he catches sight of what Bruce was referring to: a smooth, rounded section of the wall that Clark had assumed was just natural Kryptonian design, but upon second glances looks kind of like… a mirror?

“Huh,” Clark says. “And here I thought you just wanted to hang out with me in a closet.”

The mirror, like most things Kryptonian, has a rounded, organic shape, but it’s not like any silver or aluminum-coated glass mirror that Clark has seen before (and such a thing would be suspiciously out of place anyway, given that one of Krypton’s most notable features is… or was... an overwhelming lack of metal). It appears to be made entirely of black glass, with an ornate border that stands out so obviously against the carved walls that Clark can’t help but wonder how he missed it in his initial sweep of the room.

Bruce makes an amused sound, the ghost of a smile tugging at his lips in the mirror’s reflection. The visual strikes Clark as strange: the room surrounding them is out of focus, dull and hazy, like their surroundings have been intentionally blurred, yet in the centre of the mirror Clark and Bruce’s reflections are clear and bright, reflected with such pristine clarity that there may as well be carbon copies of Bruce and Clark standing before them.

“Well, I thought Kryptonians weren’t supposed to be vain.” Bruce catches Clark’s eye in the mirror, and Clark grins sheepishly at him, picturing the needlessly ornamental garments stowed on the ship, ancient clothing with intricate designs woven into the fabrics and layers of decorative adornments. 

“I think we’re all guilty of wanting to see ourselves, deep down,” Clark says. He doesn’t mean for it to sound nearly as introspective as it does, but the Kryptonian culture of vanity and self-expression is a thought he’d like to explore at a later time. “Hey, ship? What is this thing?”

“Before the creation of the liquid geo display technology, many Kryptonians utilized a reflective crystal surface to create a chiral display of the beholder,” the ship replies. 

Clark was hoping for something more simplistic, but Bruce simply nods as if that particular arrangement of words makes perfect sense. “What happened after the liquid geo was invented?”

“The technology became obsolete,” the ship says.

Clark raises his eyebrows expectantly and catches Bruce’s eye in the mirror. “So…?”

“Just a mirror,” Bruce says. “An old one, from the sound of it.” He tilts his head, examining his reflection from a few different angles. The light from the ship gives the matte material of his cowl a dull shine, but the mirror doesn’t seem to catch it. “But why keep an old mirror in an empty room?”

“Good question.” Clark steps around him, furrowing his brows at the murky reflection of the room. It doesn’t appear to be a matter of depth; even up close his reflection remains clear, while the room (and now, curiously, Bruce) have darkened like muddy water, leaving only the image of Clark in the centre. “And why conceal the room until now?”

He tries to focus on the wall beyond the mirror, but nothing changes.

“Huh.” He lifts a hand and traces his fingertips over the smooth reflective surface. “I wonder what it’s m—”

Underneath his fingers, the mirror cracks.

The sound echoes in the room, so sharp that it almost hurts Clark’s ears. He jerks his hand away as another crack appears in the glass, then another, spiderwebbing out from the spot that Clark’s fingers touched. Smaller cracks grow like small branches, turning the entire surface of the black crystal into smaller and smaller fragments until the cracks render Clark’s reflection nearly unrecognizable.

The crackling stops suddenly, pitching the room into near-silence, but Clark only has time to take a breath before the mirror shatters. The world seems to slow; the broken pieces of the crystal fall away from the frame and toward the floor in a hypnotic cascade of black, like fresh dirt falling to the ground, pattering softly against the lid of a coffin—

and suddenly Clark’s back is against the wall and he’s looking not at glass but at Bruce’s black-rimmed eyes. He can taste pine and stale earth in the back of his throat.

“Clark,” Bruce says quietly. Clark blinks at him. There’s a ringing sound still echoing in the room, but he focuses on Bruce’s voice instead, pulling it apart from the mechanical distortion of the voice modulator like a wire from a cable. “Clark, are you with me?”

One of Bruce’s hands is wrapped around Clark’s arm, and Bruce has positioned himself in such a way that his broad shoulders block out the rest of the room. 

Clark takes a breath, exhales through his nose. The lingering pine and earth taste-scent begins to fade. “Yeah. I am.” 

He finds that it’s difficult to recall just how Bruce moved him to this location, and it takes another deep breath before he actually believes his own reply. He offers Bruce a small smile, and while Bruce doesn’t seem convinced, he looks relieved that Clark’s full attention is finally on him. 

“Good,” he says quietly. He squeezes Clark’s arm gently, then glances back at the wall across the room. “We should get out of here. It’s probably time to go home.”

Clark looks over one broad caped shoulder. The ornate frame that had held the mirror is now empty, and at the base of the wall the black crystal glitters in a black heap. He remembers the mirror breaking, sure, but like his reflection in the mirror, something seems odd about the broken pieces. They look nothing like shards of mirror, he realizes. The pieces are too fine, the pile too neat. It looks more like a pile of black sand than the remnants of a mirror.

And it’s moving.

“Bruce,” Clark whispers.

Bruce looks at him, then looks at the ground.

The pile of crystal sand has begun to lose shape, sliding across the floor and pooling out like liquid obsidian, as though it were held together by surface tension until now. As if hitting some unseen barrier, the puddle of black slows to a stop, then begins to do something even more peculiar: the crystal pieces begin to pour up, hissing softly up into the air like an hourglass in reverse. 

One pillar forms, then a second begins to rise out of the floor several inches away, growing in size until it seems impossible that these shapes should exist; it reminds Clark of the ship’s liquid geo display, the way its thousands of tiny particles coalesce from all corners of the room, only the black crystal is forming this display. 

Clark stares, transfixed, as the pillars of black crystal grows taller and taller, taking the distinct shape of neither an hourglass nor the mirror, but of two legs, then a torso, then arms, then a head.

Bruce tries to step in front of Clark, but even he stops in his tracks, staring wide-eyed at the crystalline figure in front of them as it rises to its full height, just over six feet tall, practically eye-level with Clark and Bruce both.

“Bruce,” Clark says, only—

Clark doesn’t actually say anything.

The thing made of black crystal does.

**—**

Bruce sidesteps and tries to put himself between Clark and the thing standing before them, but it’s as if he isn’t even there. Clark brushes him off wordlessly, stepping toward the humanoid made of glass. To Bruce’s surprise, the humanoid figure takes a step forward, too, easily falling into sync with Clark until they’re both in the centre of the room, less than a few feet away from one another.

Bruce rests a hand on his belt and warns, “Clark…”

“It’s fine,” Clark says without looking back. “Just wait.”

Clark, while unnervingly calm, is not nearly as adept at deactivating Bruce’s sympathetic nervous system as he thinks he is, but Bruce trusts him enough to hold off on making any big moves just yet. It still doesn’t prepare Bruce for the second voice that comes from the humanoid, an echo of Clark’s reassurance, _just wait_. The entity has a black hole on its head where a mouth should be, and it moves like a mouth, closes like one, but leaves no visible seam.

Clark takes another step forward. The black figure does the same. Bruce’s fingers twitch against his belt, and he begins to circle slowly around the side.

“I think it’s…”

“...mirroring me,” the figure finishes in Clark’s voice. With the distance closed between them, Bruce can see the way its smooth body reflects Clark’s features: the red and blue of his suit seems to curve unnaturally across its chest, and Bruce can see the cautious furrow in Clark’s brow reflected just off-centre on what one might call its face. The thing begins to hiss softly as a wave of black particles slithers from its shoulders and down its back, forming a rippling sheet of black that pools on the floor.

Like a cape.

Bruce’s mouth goes dry, and he manages to flip open a single compartment in his belt before the black figure pushes off from the ground and launches itself without warning into the air, slamming into the room’s ceiling and leaving a sizeable hole in the ship. Clark looks stunned, fists already clenching as he prepares to jet off after it, but he turns his head when Bruce reaches out and grabs him by the arm.

“Clark, you need to be careful,” Bruce tells him, low and urgent. “We don’t know what it wants—”

“We don’t have time to find out,” Clark says. He places his hand briefly over the back of Bruce’s own. Bruce can’t feel the warmth of his skin through the gauntlet, but he can feel Clark gently squeezing his fingers, a silent reassurance. “I need to make sure it doesn’t get away. If I need your help, you’ll know.”

A dozen thoughts flicker through Bruce’s mind—visions of Clark hurtling through the sky with Zod at his heels, of the creature called Doomsday pummelling Clark into the ground and flinging him miles away with unparalleled strength, a memory of how Clark had looked, lying lifeless in Doomsday’s open palm—but before he can protest, Clark has already departed the ship, leaving Bruce to swear under his breath and aim his grapnel through the hole in the roof.

It only takes seconds to grapple out of the ship, leave the containment facility, and emerge into Heroes Park proper, but there’s no sign of Clark or the black figure against the dark night sky.

He listens for the sound of windows breaking, swings in a circle to look for toppling buildings or sirens wailing, but the city is asleep, blissfully unaware that something has been lying dormant in its centre for years.

“Clark!” he yells, but he isn’t waiting for a response. He’s searching for higher ground, looking to a nearby tower crane that he grapples up to without hesitation. On the jib he has a view of a greater portion of the city, along with the containment facility and the entirety of Heroes Park below.

Even from above, nothing jumps out at him. He can hear the dull roar of an airplane passing by far overhead, and he scans the sky with infrared vision to pick up any thermal signatures that might have evaded detection, but he can see no movement among the stars. No Clark, no black figure.

The city is silent and peaceful, right up until a sonic boom echoes overhead.

Bruce’s head snaps up in time to catch a Clark-shaped blur hurtling from the sky. His cape seems to be caught beneath him, flapping furiously in the wind as he plunges and slams into the ground, cratering the pavement with a noise like a small bomb detonating.

It echoes through the city, and Bruce finds himself frozen in place as a second sonic boom thunders over the city, followed shortly by a similar red-and-blue blur that speeds downward before disappearing into the cloud of rubble and dust.

The second impact shakes the surrounding park like a minor earthquake, and Bruce has to hold onto the crane until it steadies itself. He can’t see through the cloud of dirt below, but it takes no time to flip his cowl lenses into place and scan the ground with infrared vision. Most of what he can see is cool blue, but in the approximate location of the centre of the crater he can make out a single unmoving yellow-orange heat signature lying motionless beneath him. A creature made of crystal wouldn’t have a heat signature, and it’s that thought that alarms Bruce the most as a second spot of colour begins to blossom near the first signature, bleeding pink, red, and then gold with warmth until this second signature is nearly indistinguishable from the first.

There’s a sudden sinking feeling in the pit of Bruce’s stomach, and without waiting for the figures to move, Bruce flips up his lenses and leaps from the crane. The dust swirls in his wake as his cape snaps open and allows him to glide into a landing that’s somewhat easier on his knees than a direct drop, but most of the rubble has begun to settle and the dust is starting to clear. The crater is an alarming several meters deep, filled with shadows and only dimly lit with the light from the moon and the nearby construction site, but he can make out a single moving figure at the bottom of the hole struggling to its feet: Clark. 

Bruce exhales, then looks at the figure lying next to Clark, which is—horrifically, _impossibly_ —also Clark, groaning softly as his eyes finally blink open.

“Jesus Christ,” Bruce says, and both Clarks turn their heads toward him.

 

After the Doomsday incident, Lex Luthor’s green kryptonite had been secured in a location only known to three people: Bruce, Alfred, and Diana. After the day of Clark’s return, Bruce had confided in a fourth: Clark, of course, who deserved to know where his most capable enemy had hidden his most precious weapon. It hadn’t been Bruce’s decision alone to remove a sample of the kryptonite from storage to use as a failsafe; even Clark knows that most of the world’s greatest tragedies are tied to Kryptonian attacks, and the potential for other Kryptonian threats still looms over them in the form of the Phantom Zone, a creation that Bruce would never have believed possible if he hadn’t heard it directly from the scout ship itself.

Even with Clark’s approval, carrying kryptonite feels like Bruce is carrying a loaded gun without a safety mechanism. One small accident in the field could mean the difference between life and death for Clark. On the other hand, carrying it on his person doesn’t necessarily mean that Bruce will be required to use it, and it’s telling that Diana and Clark and the rest of the League consider him trustworthy enough to wield a weapon capable of killing Kryptonians.

He doesn’t like it, but carries it like he carries Clark’s faith: metaphysically close to his heart, but physically in a lead-lined pouch in his utility belt designed to not only shield Clark from its presence, but also to conceal the actual amount he carries on him. 

Clark wouldn’t know if Bruce is carrying a small vial of dust or a palm-sized chunk, but once he’s exposed to it, it shouldn’t be difficult to tell which Clark is which.

“Bruce,” the Clark on the ground calls. He’s flat on his back, slowly pulling himself upright, but he doesn’t have time to struggle to his feet before the second Clark calmly kneels in the dirt, wraps an arm around his neck, and lifts him up into the air.

“It’s a mirror image,” the second Clark announces. He pulls the other Clark effortlessly out of the crater and sets him on the pavement next to Bruce, who is already attempting to catalogue physical differences between the two in an attempt to judge which of the Clarks is which. “Like the ship said. It’s a display of the beholder.”

The cosmetic differences are frustratingly few. The Clark being held in a headlock has mussed hair and a too-familiar scowl on his face, while the calmer Clark narrows his eyes in the same distasteful manner that Bruce has seen so many times. Even Clark’s immense strength is no longer a viable indicator. Just when it looks as if the locked-in Clark is about to pry the arm away from himself, the Clark holding the headlock tightens his grip and twists the captive Clark’s arm behind his back, which means Bruce doesn’t have a chance in hell of identifying him physically.

And that heat signature. Bruce can’t stop thinking about it. It’s like the crystal figure has realized that it must mimic Clark’s appearance _and_ his physiology. What’s next? Memories?

“Pretty good for a mirror image,” the Clark in the headlock says, wincing as his arm is pulled into place. “But not the real thing.”

The non-captive Clark stares at the back of the other Clark’s head, mouth twisted into an unforgiving frown. Bruce has seen this expression before. Clark’s emotions run just beneath the surface, and Bruce has seen him wrinkle his nose at too many unsavoury stories not to recognize it. “I don’t know what this thing is or what it wants, but if it can learn to take someone else’s appearance, it can probably learn—”

“It’s definitely Kryptonian,” the captive Clark interrupts. His voice is strained, like the pressure on his windpipe is interfering with his speech. “You know what we—” 

The muscle in Clark’s arm bulges as he squeezes tighter, causing the captive Clark to gurgle angrily. It reminds Bruce of Clark’s windpipe slowly collapsing beneath his boot.

Christ, he hopes that thing doesn’t react to kryptonite.

“Is there a reason I should believe you’re the real Clark?” Bruce asks the standing Clark. He rests his hand on the compartment where he stores his smoke bombs and watches both Clarks’ eyes; the Clark he’s addressing glances down and looks at Bruce with a raised brow. The captive Clark, who has apparently given up on trying to breathe or speak, catches Bruce’s eye for just a moment, then flicks his gaze toward a compartment on the opposite side of Bruce’s belt.

Good, Bruce thinks. Keep doing that.

“I can tell you what I saw when I left the ship,” Clark says. “It was normal when you saw it, right? Just like a mirror. But when I approached it, it attacked me, and that’s when it started to change. I think when it touched my skin—”

“—Of course I moved first,” the other Clark wheezes, “that thing tried to freeze me—”

“—and _it_ tried to freeze me back,” the non-captive Clark says louder, holding Bruce’s gaze for emphasis. He has Clark’s eyes, right down to the heterochromic segments of brown. Unfortunately, the other Clark does, too. “Bruce, it’s been able to replicate every ability I‘ve shown it. We have to do something about it. I can’t let something from my world walk freely in this one.”

Bruce steps forward and looks first at the dominant Clark, then the restrained one. He’s going to have to act fast; the distant sound of sirens tells him that their terraforming project hasn’t gone unnoticed.

“Based on my last encounter with a Kryptonian, I think I have to agree,” he says, then turns his attention to the restrained Clark. “Can you tell me why you tried to freeze him back?”

“The mirror, Bruce,” Clark rasps. The non-captive Clark isn’t sympathetic enough to give him space to breathe. “I wanted to break the mirror.”

Bruce nods. The other Clark’s brow is furrowed in thought, but Bruce can't discern what he’s thinking. “What did you think would happen if you were right?”

The captive Clark seems to struggle for words, and his brows draw inward, too. “If I—you mean if I broke it? I thought it would shatter like the mirror did.”

Would a mirror creature know if it had shattered? “So you thought it would break into little shards on the ground?”

“If it looks like a mirror, it should break like one,” the immobile Clark affirms.

Bruce nods slowly, then gives this Clark a tiny, reassuring smile. He hasn’t moved his hand from his belt, and he’s starting to get a clearer picture. “Right. Now, don’t take this the wrong way, but what do you think would happen if I broke you?”

“Bruce, do you really think this is necessary?” asks the non-captive Clark. 

Bruce flashes him the same smile. “I think it’s quite necessary. You want me to make the right decision, don’t you?”

The Clark in the headlock blanches. “What are you planning to do?”

“Nothing,” Bruce says. “To the real Clark. So I need to know which one of you bleeds, and I need to know now.”

“You know I’ll bleed. You already tested that hypothesis,” the locked-in Clark says. He’s starting to look extremely nervous about Bruce’s hand placement. The Clark behind him glances once more at Bruce’s hand, but when he meets Bruce’s gaze, he simply nods.

“I trust you. Just make it fast.”

Bruce clears his throat, then looks at the restrained Clwrj once more. “One more question. If I open him up”—he nods at Clark behind—“what’s going to fall out? Glass or blood?”

The Clark Bruce is addressing looks offended, suddenly. He even pauses to look at the Clark behind him, like he can’t believe this is the situation he’s in. “Seriously? If you have to ask me, are you really sure you should be making this decision?”

He has a point.

Bruce takes a step back and stares at the pair of them, but before he can make a move the pair of Clarks rocket into the air and slam back into the ground, cracking the pavement around them yet again. It doesn’t take long to find out who’s responsible: the Clark being restrained is struggling against the other Clark’s hold, his eyes wide and fixed on Bruce’s hand. It looks as if it’s taking all of the other Clark’s strength to hold him in place.

“Hey, Bruce, I know you have to make this decision, but—maybe there’s a better way, if we can just—”

“ _Bruce_ ,” the other Clark hisses, squeezing his arms tight around the other Clark’s torso to keep his arms pinned to his sides. “I don’t want to be impatient, but you need to do something before the police get here. And please,” he adds, just a bit quieter, “don’t make the wrong choice.”

[Aim for the back.](https://archiveofourown.org/works/15394188/chapters/35728557)

[Aim for the front.](https://archiveofourown.org/works/15394188/chapters/36086910)


	2. Aim for the back.

“Hold him,” Bruce commands, and in the same moment he produces a batarang, feels it whisper against his palm when he takes a step forward and sends it spinning through the air.

A glowing green edge glints in the light from the overhead crane, and the kryptonite-tipped batarang embeds itself in the neck of the mirror creature still pinning Clark in place, just above the blue neckline of the suit, slicing into him like a knife into warm butter.

Wide-eyed and pale, the mirror creature stares at Bruce. Its skin is tinged green where the kryptonite lights it up. The world seems to go still while the creature clutches at Clark, whose head is turned down and away from the glow of the kryptonite. The city is quiet in the background, still asleep as the creature releases its hold on Clark and brushes its fingers against the place where batarang meets skin.

Its fingers come away wet, glittering black in the moonlight. Then it looks at Bruce. 

“No,” it says in Clark’s voice, “Bruce, no.”

It stumbles forward and drops to its knees, manages to pull the batarang free even though it will do no good. Bruce can see the kryptonite dust glittering around the wound as black fluid bubbles out from it. It’s a satisfying sight, in an uncomfortable sort of way; it reminds Bruce of cutting Clark open with the spear’s sharp edge, of how Clark’s body failed to close the wound and heal itself in the mere presence of the kryptonite’s radiation. He’d been satisfied by that fact at the time. He was right about Kryptonians bleeding all along.

Now Bruce just needs to make sure they know how to die.

Clark is already upright, moving back behind Bruce, kicking aside rock and dirt as he moves away from the dying creature and the kryptonite batarang. Bruce stops to place a hand on his shoulder, long enough to ensure that Clark is warm and alive and not a mirror creature made of black glass, then kneels down to pick up the batarang.

“Bruce,” it whispers. It reaches for Bruce with a black-covered hand, breathing shallowly, convincingly. “Please. Don’t. You’re making a mistake. This thing sounds—it’s not me, it’s tricking you, please—”

Bruce grips its hair and tugs its head upright, staring down with contempt. He has to admit, it’s doing an excellent job of mirroring Clark. Those eyes, soft and blue and wide with shock. And his voice, the ragged sound of his breathing, the way he clutches at the hole in his neck as if to hold it shut… it’s almost too _good_ an imitation, too similar to the terror he’d seen in Clark’s eyes when—

but had he seen terror in Clark's eyes that night? Or had Clark simply glared at him, like now, courageous even in the face of certain death?

He remembers the kryptonite scratching against Clark’s cheek, scraping away the last of Bruce’s pity for any and all things Kryptonian. 

“Bruce,” the thing that is not Clark whispers. “Don’t do this. You _know_ me.”

With a grimace, Bruce flips the batarang in his free hand, smearing black blood over his gloves to present the second green-tipped edge, a magician performing his favourite magic trick.

“I know you’re not Clark,” he says, and drags the blade across its throat.

Clark remains respectfully silent as the creature gurgles, fumbles at Bruce’s wrist, and finally slumps to the ground. A puddle begins to form beneath its body, oozing slowly across the pavement like an obsidian lake in the moonlight. Bruce stares at it, transfixed, until a hand slides over his shoulder.

“Hey,” Clark says softly. “We need to go.”

Bruce glances around. The sirens are all around them now, and he can see the red-blue flash of lights coming from all sides of the park. “We need to go to the ship.”

“The ship?” Clark echoes.

“It's the only place we can take it. They won't follow us in.” Bruce kneels down and slides his hands underneath the creature’s body. It’s surprisingly heavy. Bruce had almost expected it to feel hollow, fragile. Maybe to shatter into a million little pieces, pouring black sand onto the ground, but it just hangs limply in his arms, dead weight. It makes him think of fire and ash and a sacrifice the likes of which the world would never see again.

 

The Kryptonian ship aids them at Bruce’s command, presenting a smooth table for him to rest the body on while Clark stands nearby and frowns at the scene.

“Run diagnostics,” Bruce tells the ship. There’s an affirmative sound, then a number of small, metallic tendrils snake out of the ceiling and insert themselves into the creature’s arms and neck like intravenous tubes.

“Now commencing biological analysis,” the ship announces. 

Bruce rests his hands on the table and closes his eyes. As much as he appreciates the Kryptonian technology contained within the ship, he positively despises the lighting. The creature’s blood still looks black on his gloves, but Bruce’s fingers leave streaks of vibrant arterial crimson on the table.

They wait in silence while the ship performs its analysis. Bruce has to turn away. Even with Clark standing there, it's hard to look at the corpse and not think about what might have happened if he'd made the wrong choice. Clark is not the only one who still thinks about the night of the Doomsday incident.

“I don’t know if he deserved it,” Clark says, breaking the quiet at last. His voice sinks into Bruce like a comfortable heat in the dead of winter, and Bruce has a hard time not reaching for his arm or his hand or some other part of his body, just to reassure himself that Clark is still next to him.

“What do you mean?”

“It was… I don’t know. Violent. It didn’t feel right.”

It feels more right than letting such a creature live, Bruce doesn’t say. A being that could imitate appearances, abilities… Clark is the only Kryptonian Bruce trusts, and even that has been hard-earned. He doesn't relish the idea of killing Kryptonians, but there’s only one way to ensure that something so powerful won’t attempt to destroy the world.

The ship chimes and the tubes retract. “Analysis complete. Kal-El of Kandor, what do you wish to do?”

Clark folds his arms over his chest and stares down at the body, a deepening furrow in his brow. “I know you would have preferred to keep him alive.”

“We’ve seen what Kryptonian things are capable of doing, Clark,” Bruce says quietly. “We had no reason to suspect it would be any different this time.”

Clark nods. No argument follows. He’d nearly died at the hands of Zod twice. The last members of his species would have killed him and everyone else on the planet without a second thought. Bruce would never wish such resignation on anyone. “How did you know who to choose?”

Bruce drags his gaze away from the blood on his gloves and meets Clark’s gaze, though his face is mostly unreadable. He doesn't look pleased that Bruce was right, nor does he look upset about watching another thing from his home planet die. Crystal-based mirror image or not, it spoke like Clark and seemed to feel pain like Clark, and it can't be easy to watch something that looks like you die.

“Your voice. Your face. But it was the kryptonite, the way you reacted,” Bruce says after a moment. “That thing... it didn't even blink. But it sounded...”

He exhales just as the ship asks, “Analysis complete. Kal-El of Kandor. What do you wish to do?”

Clark offers a soft, sympathetic smile. “I know, Bruce. I imagine it was a difficult choice to make.”

Bruce looks down at the creature on the table again. Difficult isn't even the word for it. If somehow he were wrong...

He closes his right hand into a fist. The creature’s blood shines red in the ship’s soft light.

“I'm certain I made the right one,” he says, then clears his throat. “Ship, report analysis.”

“Analysis complete. Subject identified as Kal-El of Kandor. What do you wish to do?”

Bruce pauses and glances at the table, then at Clark, who raises his eyebrows in response. He doesn’t seem to be bothered by the corpse of something that looks identical to him. Even the kryptonite doesn’t seem to be affecting him.

“Perform… detailed genetic analysis,” Bruce says hesitantly. “I want to know what this thing is.”

“Analysis complete. Subject identified as Kal-El of Kandor,” the ship insists.

For the first time since the creature dropped to the ground, Bruce feels a cold wave of uncertainty wash over him.

“That… can’t be right,” he says, staring at Clark. “It only looks like… Clark.”

Clark looks up, seeming to notice for the first time that Bruce has been watching him brush his fingers through the dead thing’s hair. He smiles down at it, that shy, easy Kansas grin, and leans over the table. “Hey, don’t feel bad about it. You would have done the same thing in my place.”

Bruce blinks at him.

“What do you wish to do?” The ship repeats.

Clark straightens up. “Dispose of the body. We won’t need it.”

Another cluster of tendrils reaches down from a newly-formed hole in the ceiling, obediently curling around the corpse and lifting it away before the ceiling seals itself shut, shielding the red of Clark's cape from view.

The table disintegrates as the liquid geo disperses, leaving an empty space between Clark and Bruce. Bruce takes a step back.

“No.”

Clark shrugs, a lazy lift of his shoulder. “You don’t want to preserve him, do you? I can understand how keeping the suit would be sentimental, but keeping the whole body...” He makes a face, as if repulsed by the thought. “Listen, we… oh, you won't need that. There's no reason for dramatics.”

There’s a fresh batarang in Bruce’s hand. He barely remembers pulling it out.

“Tell me you’re Clark,” he says. The modulator covers up any tremors in his speech, a small mercy that he's thankful for. Bruce isn’t sure he could stand to hear himself waver on such a command.

“Bruce, come on, don’t...” Clark sighs, the last of his good cheer visibly fading as Bruce pulls out his batarang. “Seriously. We don’t need to… hm. Okay.” 

The batarang embeds itself in his chest with a dull thud. Clark looks down at it, grimacing in the glow of the kryptonite edge.

“I think that’s enough.”

Clark wraps his fingers around the batarang and pulls it free, seemingly unbothered by the radiation that would have crippled any other Kryptonian. At least Bruce’s aim was better the second time around: there’s a hole in Clark’s chest where the blade sank deep, but unlike the first Clark’s wound, this hole isn’t bleeding.

Unlike the first Clark’s wound, Bruce can see nothing but glittering black inside, like a million tiny pieces of glass.

“Here’s what we’re going to do,” the thing that isn’t Clark says. He doesn’t drop the batarang, and it makes his fingers glow a sickly green. “I’m going to pretend you didn’t do that. You’re going to pretend that nothing unusual happened tonight.” 

Bruce finds himself wordless, his stomach roiling with emotions that he can’t and is unwilling to to comprehend. If this thing standing in front of him isn’t Clark, if it’s not affected by the kryptonite…

if Clark is...

“Don’t do something we’ll both regret,” the creature says calmly, as if it hasn’t just ruined Bruce’s life. 

As if it hasn’t just taken Clark’s.

Bruce bares his teeth in a snarl and lunges. He’s beaten a Kryptonian before. They’ve defeated Apokoliptian generals. A thing made of glass, or crystal, or what the fuck ever should be easy to shatter with his fist, and yet every blow he lands—and he lands them, every single one, punch after punch while it stands there, taking each hit, watching him with Clark’s calm face and Clark’s calm eyes—does little more than make his knuckles ache.

The creature says nothing until Bruce has nearly winded himself; even then it doesn’t speak, just lifts its hand and catches one of Bruce’s fists in its own.

“I didn’t want to do this,” it says. The creature’s face begins to shimmer and melt, becoming a smooth surface devoid of human features. Bruce can see his own face reflected on the crystal surface, his teeth bared in his rage, his features distorting until at last the creature's face takes on a new set of characteristics: familiar brown eyes and a prominent chin, a dark helmet with two small, angular protrusions. “You can still let this go. We can act like none of this ever happened. You don’t have to lose him. He wouldn't want you to do this.”

It speaks now with the Bat’s mechanical growl. Bruce remembers feeling so helpless only a select few moments in his life. Funny enough, it always seems to happen when he’s just lost someone.

“I’m going to kill you,” Bruce whispers to the perfect copy of the Bat standing before him.

“No,” it says simply. The corner of its mouth pulls up in what a near-perfect imitation of Bruce’s own smirk. “But you’re going to wish you had.”

End

**Notes for the Chapter:**

> [The past is never dead. It's not even past.](https://archiveofourown.org/works/15394188/chapters/35728389)


	3. Aim for the front.

“Hold him,” Bruce commands, and in the same moment he produces a batarang, feels it whisper against his palm when he takes a step forward and sends it spinning through the air.

A glowing green edge glints in the light from the overhead crane, and the kryptonite-tipped batarang embeds itself in the neck of the mirror creature that Clark has pinned in place, just above the blue neckline of the suit, slicing into him like a knife into warm butter.

Eyes narrowing in irritation, the mirror creature stares at Bruce, its skin tinged green at the neck where the kryptonite lights it up. There’s a moment where the world seems to go still, and as the colour drains from Clark’s face, the creature wrenches itself out of Clark’s grip and straightens up to its full height.

With a sigh that sounds downright disappointed, the creature wraps its fingers around the batarang and tugs it free, but no rush of blood follows; Bruce can see almost directly into the wound, a dark hole that glitters in the moonlight like the inside of a geode. 

“Here’s what we’re going to do,” the thing that isn’t Clark says. The kryptonite makes its fingers glow a sickly green, but it doesn’t drop the batarang. “I’m going to pretend you didn’t do that. You’re going to pretend that—”

Whatever it was going to say is lost as Clark slams into the creature from behind. The batarang clatters from the ground as Clark and the creature both disappear into the depths of the construction project. Bruce can’t see where they’ve gone, but he can hear wooden boards snapping and steel beams groaning.

Perhaps more alarmingly, he can hear the wail of sirens beginning to approach the park.

Suddenly, one of the Clarks shoots out of the construction and into the air, with the second already hot on his heels. The uppermost Clark turns in midair and lets loose a blast of heat vision that rips into the ground and through the construction site, but the Clark below is just as quick to dodge and respond with a blast of his own, rending the sky with twin beams of fire before the first Clark hits him head-on and begins to grapple with him high above the city.

It’s nearly impossible to tell from this distance which is Clark and which is the mirror image. They fly the same, fight the same, appear to share the same strength and powers—even the dark slit that Bruce had opened in the mirror’s chest seems to have disappeared, effectively removing all certainty as to which may be the true Clark. They’re titans dancing in the sky, wrestling and slamming into one another with concussive forces that ring out like thunderclaps across the park, and all Bruce can do is stand on the ground and watch, like—

like the Black Zero event. Like Doomsday. This is the reason they formed the League. Powerful beings, threats to the world, they can’t be allowed to go unchecked, and sometimes it takes more than one person to finish the job. Bruce can’t handle this on his own, and it looks like Clark’s powers are too evenly-matched for him to gain any ground.

But together?

Scooping up the discarded batarang, Bruce grapples quickly up to the crane he’d been standing on before the Clarks had slammed into the ground. The Kryptonians have contained their fight to the air over the park, luckily, but the park is close to residential neighbourhoods and the city is filled with sleeping people. Helpless people. The thought reminds him of the first time he saw Kryptonian heat vision melting through skyscrapers, and he has to fight to suppress a shudder.

“Clark, you need to get it out of here. Take it upstairs.”

Bruce doesn’t raise his voice above a whisper. It’s low enough that the modulator barely picks it up, and hopefully low enough that the mirror creature doesn’t hear it, either. He knows Clark does; he knows because Clark always hears him, and he knows because Clark raises a hand in his direction, suddenly stops in mid-air, and rockets upward into the stratosphere.

It would be more helpful if Clark had a way to respond to him. Bruce is still working on creating long-range communication devices that don’t short-circuit the moment Clark starts to use his heat vision, and if they make it through this, he’s going to have to double down on it.

He’s also going to have to apologize for the stunt with the kryptonite, but he’ll cross that bridge when he comes to it.

“Keep going up,” he murmurs. Twin sonic booms echo far above the city as Clark follows his guidance with the mirror creature chasing behind. He watches until Clark is barely visible, until there’s no guarantee that Clark can even hear him at this distance, then says, “Take it as far out as you can. There are no nukes coming this time. You’ll need to find another way.”

Within seconds Clark and the creature are no longer visible in the night sky, but Bruce can still see the lines of light from their heat vision as they continue to trade blasts in a clash of red. During the showdown with Doomsday, Clark and the monster had created an inferno between them, illuminating the burning landscape with a brilliant light. There’s no such destruction here, luckily, and the lights are already beginning to move down on the horizon, growing fainter and fainter until they’re out of sight completely.

Christ, he hopes Clark knows what he’s doing.

*

The most jarring thing about being in space is the silence.

Clark is used to tuning out the sound of wind rushing over his ears. Sonic booms in succession are hardly noticeable, and even the aerodynamic sounds of nearby airplanes are white noise. In space, there’s none of that; no wind whistling by, no thunder to herald his arrival, no airplanes rattling his chest with their vibrations.

No sound at all.

Even the familiar whine of his heat vision is silenced in the vacuum of space, and Clark doesn’t notice that the mirror-Clark is using it until he feels the blunt force of it hit him square in the back. It sends him reeling off balance, but he’s quick to regain his footing and continues his trajectory high above the planet. At this point, he and the mirror are far enough away and moving so quickly that the earth almost seems to be standing still. 

Even Doomsday hadn’t been able to follow him out this far. Quite frankly, it’s alarming that the mirror’s newfound abilities are nearly as powerful as his own, but Clark is still going to hold his breath (he’s _literally_ holding his breath, still holding onto the deep inhale of ozone he’d managed to get before leaving earth’s atmosphere) and hope that his plan is going to work.

The mirror had sounded so factual, so like him that it had been chilling to listen to. Not that it isn’t chilling to look at something wearing your face, or listen to something that speaks with your voice, but his dislike for this creature goes beyond its attempt to appeal to Bruce, the one person who could kill him if given the chance. No, it’s the familiarity of this situation that Clark hates. He’d taken Zod into space twice. He’d knelt with his arm around Zod’s throat, knowing that if he let go, he would doom the planet.

He hates this creature for wearing his face, but he hates this creature more for what it hasn’t yet done—and so he hurtles toward the sun with the mirror blasting him with heat, determined to put an end to the threat of yet another Kryptonian. 

If it looks like a mirror, it should break like one, the mirror said to Bruce.

Clark typically tries not to rely on last-ditch efforts anymore, but this time he’s banking on that being true.

The sun is a gargantuan wall of light and plasma and blistering heat, but neither Clark nor the mirror slow as they approach it. In fact, Clark does quite the opposite: he breaks the speed of light and barrels headlong into a lick of flame that he vaguely thinks might be a solar flare, but he doesn’t stop to worry about the specifics. 

Then he stops.

The mirror slams into him with enough force to send him spinning what feels like several miles closer to the sun, nearly knocking his breath out in the process. At this distance, it probably doesn’t matter how close to the sun he is; the heat is so intense that even Clark feels uncomfortable, his skin prickling in a way and his stomach roiling with an unease that he hasn’t felt since the night he was introduced to kryptonite.

He’s pretty sure it’s fear. Bruce might be able to rely on the kryptonite to kill a Kryptonian creature, but Clark isn’t so sure that this mirror image is Kryptonian at all. He doesn’t know how it would react to a high dose of kryptonite radiation, but that information is irrelevant to him. 

All that matters is that he knows it’s made out of crystal.

In the immense heat of the solar flare, Clark whirls around, grabs the mirror by the head, and leans in until their faces are nearly touching. The mirror grins at him, face contorting into a sinister expression that Clark has never before seen on himself. It’s hideous, now that he sees it for what it really is, no more a mirror than a cheap imitation.

 _You’re not fooling anyone_ , Clark thinks, then forcefully expels the lungful of air that he’s been holding in his chest since their departure. 

It’s a complete shot in the dark. As far as Clark knows, nobody has ever attempted to create a small blizzard in the outskirts of the sun, and he’s not even entirely sure that it’s going to work; but while the sun’s proximity mutes his frigid breath, he can still feel the slightest temperature change in the plasma-filled space between them.

The mirror’s smile falters as Clark, now with both hands around its head, begins to squeeze.

**—**

Nearly twenty minutes after Clark’s disappearance, Bruce finds himself perched atop a nearby skyscraper, using the cover of night to shield himself from the swarms of helicopters and emergency response teams.

People in Metropolis don’t take anything lightly these days, and the sizeable hole in Heroes Park is as good a sign as any that something is—or was—happening in the city. There’s no evacuation order being given, but there’s a SWAT team on location and Bruce is fairly sure that someone in the White House is already frantically running around trying to decide what to do about the scene. But with Clark’s location unknown, there’s little that anyone can do to properly assess the threat, so Bruce simply watches the police rope off the crater and shine their lights around, waiting impatiently for something to happen. 

Which, of course, it does.

The sky over Metropolis begins to hum. Quiet at first, the hum grows into a rumble, and when the policemen on the ground begin to scatter, running back to their cars in a panic, Bruce looks up and sees the fireball.

Though it manages to avoid hitting any of the news helicopters, the fireball crashes into the centre of Heroes Park with a sound like a cannon, illuminating the surrounding buildings with a brilliant light before the cloud of debris that it raises blots it out. The impact shakes the building that Bruce is standing on and makes the ground below shudder, setting off car alarms and causing the lights surrounding the park to flicker and dim.

The smoking crater is illuminated by several nearby police and news helicopters, but when the dust finally clears he can see, standing in the centre of the pit, a humanoid figure in a cape, one arm raised against the floodlights trained on it.

“Clark,” Bruce whispers, too cautious yet to be hopeful.

The figure in the crater turns its head and looks at him, raises a hand briefly in greeting, then rises out of the crater to address what looks like the entirety of the Metropolis PD gathered around the park.

Bruce lowers himself into a crouch once more and waits.

 

It takes an hour for the park to settle down. The sky’s beginning to lighten on the horizon, and yet when Clark finally breaks away and flies up to meet him atop the building, Bruce is still wide awake.

Clark touches down on the roof silently, glances around at the silent air, and heaves a sigh of relief.

“Talk about a warm welcome. The headlines are gonna be brutal,” he says, a grim expression on his face. Bruce watches him run his fingers through his hair, shaking free loose bits of debris and dirt. “Thanks for waiting.”

“Did you get it?” Bruce asks.

Clark glances up at him. “The mirror? Yeah, I think so.”

“What did it look like? When it broke?”

This time Clark holds his gaze, eyes narrowed as if to accuse Bruce of not believing him, but the accusation never leaves his mouth. Clark just sort of smiles at him, shaking his head as he steps closer to Bruce.

“You know… I’m not really sure.”

Bruce considers that for a moment, then tilts his head forward and rests his forehead against Clark’s. He lets his eyes slide shut and inhales. 

Clark smells faintly of ozone, but of something more familiar, like hot metal, or charred meat.

“Do you want to know how I knew it was you?” Bruce asks without opening his eyes.

Clark hums quietly and rests a hand on Bruce’s arm. “Does it matter?”

“It would if I made the wrong choice.”

Clark is quiet for a moment, but he doesn’t break away. When Bruce blinks his eyes open, he finds that Clark is gazing at him, searching his face for some answer that Bruce must not be telling him.

“You have the kryptonite,” Clark says quietly. His mouth nearly brushes Bruce’s. “You can be sure.”

It would be a simple test to drag the batarang’s edge of Clark’s palm, to draw blood or black and know whether Clark is lying. But he knows also that only one Clark returned from the sky, and he fully believes that Clark has told him the truth about the culmination of their battle. He believes that the Clark in his arms is the only one left, and that what happened to the other Clark, real or mirror, is now a secret contained among the stars.

And if Bruce is to be honest with himself, he would rather accept this Clark than lose both.

“I’m sure enough,” he tells Clark, and kisses him just as the sun inches up on the horizon, illuminating them both in the first golden rays of morning.

End

**Notes for the Chapter:**

> [The past is never dead. It's not even past.](https://archiveofourown.org/works/15394188/chapters/35728389)


End file.
